Hermetic compressor

ABSTRACT

Disclosed herein is a hermetic compressor. The hermetic compressor includes a suction muffler. The suction muffler includes an inlet part and a refrigerant guide pipe. The inlet part has a shape of a semi-flare pipe, and is spaced apart from an inlet pipe. The refrigerant guide pipe extends from an interior of a resonance chamber to communicate with a compression chamber. An expanding part having an enlarged diameter is provided at an inlet of the refrigerant guide pipe. The inlet part and the expanding part allow noises produced in the compression chamber to be doubly diffused, thus efficiently reducing the noises.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No.2003-91119, filed Dec. 15, 2003 in the Korean Intellectual PropertyOffice, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to hermetic compressors and,more particularly, to a suction muffler of a hermetic compressor, whichdraws a gas refrigerant of a low pressure passing through an inlet pipeinto a compression chamber of a cylinder block.

2. Description of the Related Art

Generally, hermetic compressors are widely used in refrigerationsystems, such as a refrigerator, to compress a refrigerant. Aconventional hermetic compressor includes a hermetic casing to define ahermetic space, with a compressing unit to compress a refrigerant and adrive unit to drive the compressing unit being installed in the hermeticcasing.

The compressing unit includes a cylinder block which defines acompression chamber to compress the refrigerant. A cylinder head ismounted to an end of the cylinder block, and has both a suction chamberto guide the refrigerant into the compression chamber, and an exhaustchamber to guide the compressed refrigerant from the compression chamberto an outside of the hermetic casing. Further, a piston is installed inthe compression chamber.

The drive unit includes a stator which generates an electromagneticfield, when an electric power is applied to the stator. A rotor isrotated by the electromagnetic field generated along the stator, androtates a rotating shaft. Due to a rotating motion of the rotor, thepiston reciprocates in the compression chamber, thus compressing therefrigerant.

Further, an inlet pipe is installed at a predetermined portion of thehermetic casing to draw the refrigerant from the outside of the hermeticcasing. A suction muffler is provided at a predetermined portion of thehermetic casing to communicate with the inlet pipe.

The suction muffler functions to reduce noises produced when therefrigerant is compressed by the compressing unit, in addition toguiding the refrigerant into the suction chamber of the cylinder head.

However, the conventional hermetic compressor is constructed so that thenoises are deadened in the resonance chamber provided in the suctionmuffler. Thus, the conventional hermetic compressor has a problem inthat the noises are not completely absorbed in the resonance chamber,but some noises are released to an outside of the compressor through theinlet pipe. Thereby, the flowing direction of the refrigerant isopposite to the releasing direction of the noises in the inlet pipe,thus causing resonance between refrigerant flowing frequency and noisefrequency, therefore increasing noises and vibrations of the compressor.

SUMMARY OF THE INVENTION

Accordingly, it is an aspect of the present invention to provide ahermetic compressor which has an improved structure of a suctionmuffler, thus efficiently reducing noise and vibrations.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

The above and/or other aspects are achieved by a hermetic compressor,including a hermetic casing, a compressing unit provided in the hermeticcasing to compress a refrigerant, an inlet pipe to guide the refrigerantinto the hermetic casing, and a suction muffler to draw the refrigerantthrough the inlet pipe and to discharge the refrigerant to thecompressing unit. The suction muffler includes a muffler casing, aninlet part, and a refrigerant guide pipe. The muffler casing defines aresonance chamber therein. The inlet part is provided at a predeterminedportion of the muffler casing, and has an inlet port to allow therefrigerant to be drawn into the muffler casing, with the inlet portbeing provided to be spaced apart from the inlet pipe. The refrigerantguide pipe extends from an interior of the resonance chamber tocommunicate with the compressing unit, with an expanding part having anenlarged diameter and being provided at an inlet of the refrigerantguide pipe.

According to an aspect of the invention, the expanding part may beprovided to be tapered in a flowing direction of the refrigerant whichis drawn into the muffler casing.

In another aspect of this embodiment, the inlet port may have a shape ofa semi-flare pipe which is tapered in a flowing direction of therefrigerant which is drawn into the muffler casing.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe preferred embodiments, taken in conjunction with the accompanyingdrawings of which:

FIG. 1 is a sectional view of a hermetic compressor, according to anembodiment of the present invention;

FIG. 2 is a sectional view of a suction muffler of the hermeticcompressor of FIG. 1; and

FIG. 3 is a perspective view of a refrigerant guide pipe of the suctionmuffler of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the present preferredembodiments of the present invention, examples of which are illustratedin the accompanying drawings, wherein like reference numerals refer tolike elements throughout. The embodiment is described below in order toexplain the present invention by referring to the figures.

FIG. 1 is a sectional view of a hermetic compressor, according to anembodiment of the present invention. Referring to FIG. 1, the hermeticcompressor includes a hermetic casing 10, with a compressing unit 20 anda drive unit 30 being installed in the hermetic casing 10. Thecompressing unit 20 compresses a refrigerant, and the drive unit 30generates a power to drive the compressing unit 20.

The compressing unit 20 includes a cylinder block 21 to define acompression chamber 21 a therein. A piston 22 is received in thecompression chamber 21 a, and rectilinearly reciprocates in thecompression chamber 21 a to draw, compress, and discharge therefrigerant. A cylinder head 23 is mounted to an end of the cylinderblock 21, with a suction chamber 23 a and an exhaust chamber 23 b beingdefined in the cylinder head 23. Further, a valve plate 24 is interposedbetween the cylinder block 21 and the cylinder head 23, and includes aninlet valve 24 a to allow the refrigerant to be drawn into thecompression chamber 21 a, and an outlet valve 24 b to allow thecompressed refrigerant to be discharged from the compression chamber 21a.

The drive unit 30 is provided to reciprocate the piston 22, thuscompressing the refrigerant in the compressing unit 20. The drive unit30 includes a stator 31 which is installed in the hermetic casing 10,and a rotor 32 which is set in the stator 31 to be spaced apart from thestator 31 and is rotated by an electromagnetic field generated along thestator 31 when an electric power is applied to the stator 31. Further, arotating shaft 33 is provided at a center of the rotor 32 to rotatealong with the rotor 32. An eccentric part 34 which eccentricallyrotates and a connecting rod 35 are provided under the rotating shaft33. The connecting rod 35 is connected at a first end thereof to theeccentric part 34 and at a second end thereof to the piston 22, thusconverting the rotating motion of the eccentric part 34 into therectilinear reciprocating motion of the piston 22.

Further, a suction muffler 50 is provided on a side of the cylinder head23 to reduce noises produced by compressing the refrigerant in thecompression chamber 21 a. The suction muffler 50 of the hermeticcompressor according to the present invention will be described in thefollowing in detail with reference to FIG. 2.

As shown in FIG. 2, the suction muffler 50 includes a muffler casing 51,an inlet part 53, and an outlet port 55. The muffler casing 51 defines aresonance chamber 52. The inlet part 53 is provided at a predeterminedposition of a lower portion of the muffler casing 51, and has an inletport 54 to allow the refrigerant to be drawn into the muffler casing 51.The outlet port 55 is provided on a bottom of the muffler casing 51 tobe opened toward the cylinder head 23.

The inlet part 53 has a shape of a semi-flare pipe which is graduallytapered in a flowing direction of the refrigerant which is drawn fromthe inlet port 54 into the muffler casing 51. The inlet port 54 isprovided to be spaced apart, by a predetermined distance, from an end ofthe inlet pipe 40 which penetrates the hermetic casing 10 to draw therefrigerant into the hermetic casing 10.

Of the refrigerant passing through the inlet pipe 40, a gas refrigerantrepresented by fine solid arrows flows through the inlet part 53 intothe resonance chamber 52. Meanwhile, a liquid refrigerant represented bythick solid arrows collides against an inclined inner wall of the inletpart 53, and falls to a bottom of the hermetic casing 10 due to gravity.Thus, the liquid refrigerant is not fed through the inlet part 53 to themuffler casing 51. Further, such an inlet part 53 allows noises producedin the compressor to be efficiently reduced. The operational effects ofthe suction muffler 50 having the inlet part 53 constructed as describedabove will be described hereinafter in detail.

According to the present invention, the suction muffler 50 furtherincludes a refrigerant guide pipe 56 to guide the refrigerant from theresonance chamber 52 to the cylinder head 23.

The refrigerant guide pipe 56 extends from an interior of the resonancechamber 52 to the outlet port 55. In this case, an end of therefrigerant guide pipe 56 is connected to the cylinder head 23.

As shown in FIG. 3, the refrigerant guide pipe 56 has, at an inletthereof through which the refrigerant is drawn, an expanding part 57.The expanding part 57 has an enlarged diameter, and is provided to begradually tapered in a flowing direction of the refrigerant which isdrawn into the muffler casing 51.

The operation and operational effects of the hermetic compressorconstructed as described above will be described in the following.

When an electric power is applied to the drive unit 30, the rotatingshaft 33 is rotated along with the rotor 32. By the rotation of therotating shaft 33, the eccentric part 34 is eccentrically rotated.Further, when the piston 22 reciprocates in the compression chamber 21 aby the rotating motion of the eccentric part 34, the refrigerantsequentially passes through the suction muffler 50 and the suctionchamber 23 a of the cylinder head 23. Subsequently, the refrigerant isfed into the compression chamber 21 a to be compressed. The compressedrefrigerant is discharged to the exhaust chamber 23 b of the cylinderhead 23.

At this time, the noises produced by compressing the refrigerant in thecompression chamber 21 a are sent from the suction chamber 23 a of thecylinder head 23 to the suction muffler 50, as shown by dotted lines ofFIG. 2. The noises are sent through the refrigerant guide pipe 56 of thesuction muffler 50 to the interior of the resonance chamber 52.

Further, the noises are diffused into the resonance chamber 52 via theexpanding part 57 of the refrigerant guide pipe 56, so that the noisesare primarily reduced. Remaining noises are diffused into the compressorthrough the inlet part 53 having the shape of the semi-flare pipe, sothat the noises are secondarily reduced.

In a brief description, the suction muffler 50 according to the presentinvention is constructed to allow the noises to be doubly diffused, thusefficiently reducing the noises.

Further, the inlet port 54 is spaced apart from the inlet pipe 40, sothat the noises passing through the inlet port 54 are not sent to aninterior of the inlet pipe 40, but is diffused into the compressor, thuspreventing the noise and vibrations from being generated by theresonance between a flowing frequency of the refrigerant and a noisefrequency in the inlet pipe 40.

As is apparent from the above description, the present inventionprovides a hermetic compressor, which is constructed so that a suctionmuffler includes an expanding part and an inlet part having a shape of asemi-flare pipe, thus efficiently reducing noises produced in acompressing unit, therefore allowing the compressor to be stablyoperated.

Further, in the hermetic compressor of the present invention, an inletport of the suction muffler is spaced apart from an inlet pipe, thuspreventing noises passing through the inlet port from resonating in theinlet pipe, therefore increasing reliability of the compressor.

Although an embodiment of the present invention has been shown anddescribed, it would be appreciated by those skilled in the art thatchanges may be made in these embodiments without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

1. A hermetic compressor, comprising: a hermetic casing; a compressingunit provided in the hermetic casing to compress a refrigerant; an inletpipe to guide the refrigerant into the hermetic casing; and a suctionmuffler to draw the refrigerant through the inlet pipe, and to dischargethe refrigerant to the compressing unit, the suction muffler comprising:a muffler casing to define a resonance chamber therein; an inlet partprovided at a predetermined portion of the muffler casing, and having aninlet port to allow the refrigerant to be drawn into the muffler casing,with the inlet port being provided to be spaced apart from the inletpipe; and a refrigerant guide pipe to extend from an interior of theresonance chamber to communicate with the compressing unit, with anexpanding part having an enlarged diameter and being provided at aninlet of the refrigerant guide pipe.
 2. The hermetic compressoraccording to claim 1, wherein the expanding part is provided to betapered in a flowing direction of the refrigerant which is drawn intothe muffler casing.
 3. The hermetic compressor according to claim 1,wherein the inlet port has a shape of a semi-flare pipe which is taperedin a flowing direction of the refrigerant which is drawn into themuffler casing.